Mice exposed to stressful situations, including tilting their cages, alternating light with darkness and switchingmice between isolation and crowded quarters, have increased levels of immune system proteins in their bloodthat can cause symptoms similar to those of atherosclerosis. During stressful situations the immune systemprepares for danger by producing excess leukocytes, which interact with the protein called beta 3 formingatherosclerotic plaques. When scientists blocked the activity of beta 3 the stressed mice showed fewerdangerous plaques.http://news.sciencemag.org/biology/2014/06/how-stress-can-clog-your-arteries

Researchers have found that the ‘ERK pathway’ must be constantly active for salamander cells to bereprogrammed, and hence able to contribute to the regeneration of different body parts. The team identified akey difference between the activity of this pathway in salamanders and mammals, which helps us tounderstand why humans can’t regrow limbs and sheds light on how regeneration of human cells can beimproved.http://www.ucl.ac.uk/news/news-articles/0614/200614-salamander-limb-regeneration

A new vaccine developed by researchers in Germany boosts the immune system to protect against braintumours in mice. With the difficulty of treating brain tumours, the team at the National Center for TumourDiseases hopes that boosting the body's natural response may offer new opportunities for patients.http://www.bbc.co.uk/news/health-28013585

The monarch butterfly uses a magnetic compass to guide its extraordinary migration thousands of kilometresacross North America. Monarchs are known to possess a Sun compass but even on cloudy days they stillkeep flying south towards Mexico. In a laboratory experiment, butterflies changed direction when themagnetic field around them was altered.http://www.bbc.co.uk/news/science-environment-27909303